Polisher block swivel joint



April 28, 1959 D. R. LIMBERS POLISHER BLOCK SWIVEL JOINT Filed Feb. 24, 1958 l lllll INVENTOR D04 R L/MBERS ATTORNEY United StatesPatent O POLISHER BLOCK SWIVEL JOINT Don R. Limbers, Tarentum, Pa., assignor to Pittsburgh Plate Glass Company, Allegheny County, Pa., a corporation of Pennsylvania Application February 24, 1958, Serial No. 716,977

6 Claims. (Cl. 51-168) This invention relates to apparatus for surfacing plate glass or other flat glass sheets and more particularly to a novel means for connecting a polishing runner block to a spindle of a surfacing apparatus.

Conventional surfacing apparatus includes a rotary drive spindle and a plurality of radial arms extending from a hub connected to the spindle. Each arm is rigidly connected, by means of a vertical spindle, to a runner block to which is attached apolishing pad for contact with the glass. Each of the runner blocks is retained in a horizontal plane regardless of the surface conditions of the glass resulting in non-uniform surfacing of the glass and non-uniform wear on the pads. This invention avoids the deficiency set forth by providing a flexible connection between the runner block and the vertical spindle extending from the arm allowing misalignment therebetween to accommodate slight diflerences in surface conditions of the glass and thereby insuring substantially uniform polishing of the glass and wear of the polishing pad.

The primary object of this invention is the provision of an improved glass surfacing apparatus wherein the runner blocks are connected to a vertical spindle of the surfacing apparatus by flexible means to allow misalignment of the runner blocks to accommodate slight variations in the surface conditions of the glass.

This and other objects and features of this invention will be apparent when taken with the accompanying drawing wherein the single figure is a sectional view of part of a surfacing apparatus illustrating one of the plurality of runner blocks and having a polishing pad connected to a spindle by the flexible means.

Since all runner blocks and connections are the same, the description will be limited to the single one illustrated.

In the drawing, there is illustrated a part of the polishing apparatus, generally identified as 10, including a spider arm 12, a vertical spindle 14 and a polishing runner block 16 having a fibrous polishing pad 18, such as felt, cemented thereto.

The arm 12 has an enlarged, substantially cylindrical, terminal end defining a bearing 20 to receive a flanged cylindrical bushing 22. The spindle 14 is received within the bushing 22 and extends vertically downwardly, terminating in an enlarged, stepped end 24. The top end of the spindle 14 is provided with an opening 26 to receive a pin 28 which retains the spindle in its illustrated position.

The runner block 16 is circular in outline and is provided with a central circular recess 30 having an outwardly flanged defining wall 32, the flange 34 of which is provided with a plurality of openings 36 for a purpose to be described.

The spindle 14 at its end 24 is surrounded by a conventional ball bearing 38 which, because of its conventional construction, requires no further description. The ball bearing is locked in position by means of a lock collar 40 surrounding the spindle 14 and connected thereto by means of set screws 42. The ball bearing is received within annular, complementary grooves 44 and 46 in abutting flexible or resilient annular elements 48 and 50, respectively. The elements 48 and 50, preferably made of grease resisting synthetic rubber, are of the same external diameter as the diameter of the recess 30 and are received therein. A flanged retainer member 52 has a cylindrical portion 54 also received within the recess 30 and a flanged portion 56 provided with a plurality of openings 58 in alignment with the openings 36 in the flange 34. When bolted together with the bolts passing through the aligned openings 36 and 58, the retainer portion 54 retains the elements 48 and 50 in their illustrated positions and, therefore, provides the flexible c0nnection between the spindle 14 and the runner block 16.

A dirt seal 60 is provided to prevent the entrance of dirt or other foreign matter into the ball bearings 38 and comprises a substantially cup-shaped member surrounding the spindle 14 and having a relatively soft oil and grease resistant rubber portion 62 joined to a relatively hard rubber rim portion 64, the latter being in contact with the retainer member 52 during the entire operation of the apparatus, the different rubber portions insuring this contact regardless of the relative misalignment between the spindle 14 and the runner block 16. The choice of a grease resistant rubber for the portion 62 is dictated by the desire for long life to this portion, since the ball bearings 38 require greasing for efficient operation.

As will be obvious from the construction described, the spindle 14 will remain vertical under all conditions of operation, but the runner block 16 and pad 18 may become misaligned, i.e., may move from the horizontal position illustrated, due to the surface conditions of the glass being polished, this misalignment being allowed by the flexible connection between the block 16 and the spindle 14 provided by the members 48 and 50.

I claim:

1. In a glass surfacing apparatus which includes a spider having a plurality of radial arms, a vertical spindle connected to each arm, and a plurality of runner blocks having attached surfacing means, the improvement comprising bearing means connected to each spindle adjacent its terminal end removed from the arm, a substantially circular central recess in each runner block, and substantially cylindrical resilient means having groove means embracing said bearing means, said resilient means being received within said recess and providing a flexible connection between each of said runner blocks and their respective spindles to allow relative misalignment therebetween when required by the surface of the glass.

2. In a glass surfacing apparatus which includes a spider having a plurality of radial arms, a vertical spindle connected to each arm, and a plurality of runner blocks having attached surfacing means, the improvement comprising bearing means connected to each spindle adjacent its terminal end removed from the arm, a substantially circular recess in each runner block, resilient means com prising a pair of abutting annular members each having a complementary groove therein embracing said bearing means, said resilient means being received within said recess and providing a flexible connection between each of said runner blocks and their respective spindles to allow relative misalignment therebetween when required by the surface of the glass, and means for retaining said annular members within said recess.

3. Glass surfacing apparatus comprising a spider having a plurality of radial arms, a vertical spindle connected to each arm, a plurality of runner blocks having attached surfacing means, ball bearing surrounding each spindle adjacent its terminal end removed from the arm, means fixing each ball bearing in position, a substantially circular central recess in each runner block, and resilient means including a pair of abutting annular rubber elements having complementary grooves therein embracing said bearing means, said resilient means being received within said recess and providing a flexible connection between each of said runner blocks and their respective spindles to allow relative misalignment therebetween when required by the surface of the glass, and means for retaining said resilient means within said recess.

4. Glass surfacing apparatus as recited in claim 3, further including a dirt seal having a relatively flexible portion and a relatively rigid portion, said dirt seal being so constructed and arranged relative to said spindle and said runner block to prevent the entrance of dirt into said ball bearing in any relative position of said runner and spindle.

5. Glass surfacing apparatus as recited in claim 4,

wherein said dirt seal is substantially cup-shaped, said relatively flexible portion surrounds said spindle, and said relatively rigid portion is in continuous contact With said retaining member.

6. Glass surfacing apparatus as recited in claim 5, wherein said relatively flexible portion is soft rubber and said relatively rigid portion is hard rubber.

References Cited in the file of this patent UNITED STATES PATENTS 1,698,365 Hitchock Jan. 8, 1929 1,836,542 Miller Dec. 15, 1931 2,295,282 Mall Sept. 8, 1942 

